'Would it be cheating if I joined in?' ... Margaret Atwood responds to news of 1book140. Photograph: Murdo Macleod

From New Zealand to Brazil, India to Japan, thousands of readers around the world are coming together to tackle Margaret Atwood's Booker-prize winning novel The Blind Assassin through a global Twitter book club.

1book140 follows last summer's One Book, One Twitter club, which saw 12,000 people discussing Neil Gaiman's American Gods on the micro-blogging site. Originator Jeff Howe, author of Crowdsourcing and a professor of journalism at Northeastern University in Boston, decided to relaunch the initiative this year, in conjunction with the Atlantic magazine, and to make it a monthly virtual meet-up for readers. "One Book, One Twitter was a smash. The only problem? It disappeared, like barbecues and seersucker suits, when summer came to a close," said Howe. "Now it's back ... It has a new name – 1book140 – but what hasn't changed is the global, participatory nature of the affair: The crowd is still in charge."

More than 2,000 people nominated almost 300 books for the club's first discussion, with Atwood's mix of pulp science fiction, historical fiction and romance eventually triumphing over Gary Shteyngart's Super Sad True Love Story. Discussions about The Blind Assassin started this morning, with future titles to be selected according to a theme, said Howe: "Contemporary history, horror (yes, yes, we heard you loud and clear, Joe Hill fanatics), classic novels, etc."

"Gosh, thanks, Atlantic #1book140 voters! "(Writhes bashfully)," tweeted Atwood, learning of the club's first choice. "Would it be cheating if I joined in? Guess so ..." But readers were quick to convince her otherwise – Gaiman was an enthusiastic participant in last year's discussions of American Gods – and Atwood has already provided a "factoid" for book club members: "Bridge Laura drives off is still there, but they changed railings to solid sides."

More than 5,000 readers have already joined the @1book140 club, with general discussions taking place under the hashtag 1book140 from 1 June, and more detailed analysis of the novel's sections under the dedicated hashtags #1b140_1, #1b140_2, and so on. "Being amazed by Atwood at every turn," tweeted one reader in London; "Probably my first book written from a senior person's perspective. Never expected it to be so lovely." Added another: "Falling for the storyteller dude telling the story w/in the story w/in the story."

"This is not a book club with lots of rules and regulations. Just like last year, part of the charm lies in keeping it a little loosie goosie," said Howe. "Will some readers, having whizzed through the book, want to discuss Part V after the first few days? Of course. Will other readers want to drop back and tackle a thorny question raised in Part I at the end of the month? I hope so. The hashtags will be up from the very beginning. Use them as you see fit, and as always, 1book140, happy reading."